A color filter is used for an optical filter for devices such as a liquid crystal display (LCD), a camera, and the like, and is a thin film-type optical part extracting more than 3 colors from a white light and working fine pixel units. The pixel has a size of tens to hundreds of micrometers. This color filter has a structure of laminating a black matrix layer with a predetermined pattern to block a boundary between pixels and a pixel region including three primary colors of red (R), green (G), and blue (B) sequentially arranged in a predetermined order on a transparent substrate.
Generally, a color filter may be fabricated by coating three or more colors on a transparent substrate using processes such as dyeing, electrophoretic deposition, printing, and pigment dispersion. Recently, pigment dispersion using a pigment-dispersible color resist is mainly used.
A pigment dispersion method forms a colored film by repeating a series of processes such as coating, exposing to a light, developing, and curing a photopolymerizable composition including a coloring agent on a transparent substrate including a black matrix. The pigment dispersion method can improve heat resistance and durability, which are very important characteristics for a color filter, and can provide a film with a uniform thickness. Therefore, the method is widely applied.
Recently, a large liquid crystal display (LCD) requires high luminance and a high contrast ratio, but in order to satisfy these requirements, color reproducibility of a color filter may be deteriorated.